ASON for VS Code

Compress and decompress JSON using the ASON format directly in Visual Studio Code. Reduce token usage by 20-60% for LLM applications while maintaining 100% lossless round-trip fidelity.

Two Ways to Use ASON in VS Code

1. Extension Commands

• Direct commands for manual compression/decompression
• Keyboard shortcuts: Cmd+Alt+C (compress), Cmd+Alt+D (decompress), Cmd+Alt+S (stats)
• Accessible via Command Palette or right-click menu
• Perfect for one-off conversions

2. MCP Server Integration (Automatic)

• Automatically configured when you install this extension!
• Works with GitHub Copilot Chat (requires VS Code 1.99+)
• Copilot can use ASON tools automatically
• Ask Copilot: "Compress this JSON using ASON" and it works!
• No manual configuration needed - it just works!

Installation

From VS Code Marketplace

1. Open VS Code
2. Go to Extensions (Cmd+Shift+X / Ctrl+Shift+X)
3. Search for "ASON"
4. Click Install
5. MCP server is automatically configured for Copilot!

Requirements

• VS Code 1.99+ (for MCP server integration)
• Node.js 18+ (for MCP server via npx)
• GitHub Copilot (optional, for automatic tool access)

What Happens on Install

When you install this extension:

1. ✅ Extension commands are registered (ASON: Compress, etc.)
2. ✅ MCP server is automatically configured for GitHub Copilot
3. ✅ ASON tools become available in Copilot Chat
4. ✅ No manual configuration needed!

The MCP server uses npx @ason-format/mcp-server@latest, so it always stays up-to-date.

Features

• Compress JSON to ASON: Convert selected JSON to token-optimized ASON format
• Decompress ASON to JSON: Restore ASON back to original JSON (lossless)
• Compression Statistics: View detailed metrics on token and byte savings
• Configurable Settings: Customize compression behavior per workspace
• MCP Server Support: Use with GitHub Copilot Chat (VS Code 1.99+)

Commands

Access commands via:

• Command Palette (Cmd+Shift+P / Ctrl+Shift+P)
• Right-click context menu (when text is selected)

Available Commands

Command	Description
ASON: Compress Selection	Compress selected JSON to ASON format
ASON: Decompress Selection	Decompress selected ASON to JSON
ASON: Show Compression Stats	Display detailed compression statistics

Usage

Compress JSON

1. Select JSON text in your editor
2. Open Command Palette (Cmd+Shift+P)
3. Run ASON: Compress Selection
4. Selected text is replaced with ASON format

Before:

{
  "users": [
    {"id": 1, "name": "Alice", "age": 25},
    {"id": 2, "name": "Bob", "age": 30}
  ]
}

After:

users:[2]{id,name,age}
1|Alice|25
2|Bob|30

Decompress ASON

1. Select ASON text in your editor
2. Run ASON: Decompress Selection
3. Selected text is replaced with formatted JSON

View Statistics

1. Select JSON text
2. Run ASON: Show Compression Stats
3. View detailed metrics in the output panel:

=== ASON Compression Statistics ===

Original Tokens:    59
Compressed Tokens:  23
Token Reduction:    61.02%

Original Size:      151 bytes
Compressed Size:    43 bytes
Bytes Saved:        108 bytes

=== Configuration ===

Indent:             1
Delimiter:          "|"
Use References:     true
Use Sections:       true
Use Tabular:        true

=== ASON Preview ===

users:[2]{id,name,age}
1|Alice|25
2|Bob|30

Configuration

Configure ASON behavior in your workspace settings (Cmd+, / Ctrl+,):

{
  "ason.indent": 1,
  "ason.delimiter": "|",
  "ason.useReferences": true,
  "ason.useSections": true,
  "ason.useTabular": true,
  "ason.autoShowStats": true
}

Settings Reference

Setting	Type	Default	Description
ason.indent	number	1	Indentation level for nested structures
ason.delimiter	string	`"	"`
ason.useReferences	boolean	true	Enable $var reference deduplication
ason.useSections	boolean	true	Enable @section organization for objects
ason.useTabular	boolean	true	Enable key:[N]{fields} tabular format for arrays
ason.autoShowStats	boolean	true	Show statistics after compression

Use Cases

Reduce LLM API Costs

Compress data before sending to OpenAI, Claude, or other LLM APIs:

// Instead of sending 150 tokens
const json = {"users": [{"id": 1, "name": "Alice"}, ...]};

// Send 60 tokens (60% reduction)
const ason = "users:[2]{id,name}\n1|Alice\n...";

Optimize LocalStorage

Store more data in browser localStorage:

// Before: 2KB JSON
localStorage.setItem('data', JSON.stringify(data));

// After: 800 bytes ASON
localStorage.setItem('data', compressor.compress(data));

Compact API Responses

Reduce bandwidth for API responses:

// Server compresses responses
app.get('/api/data', (req, res) => {
  const ason = compressor.compress(data);
  res.send(ason);
});

Keyboard Shortcuts

You can add custom keyboard shortcuts in VS Code:

1. Open Keyboard Shortcuts (Cmd+K Cmd+S / Ctrl+K Ctrl+S)
2. Search for "ASON"
3. Assign shortcuts (e.g., Cmd+Shift+A for compress)

Example keybindings.json:

[
  {
    "key": "cmd+shift+a",
    "command": "ason.compressSelection",
    "when": "editorHasSelection"
  },
  {
    "key": "cmd+shift+d",
    "command": "ason.decompressSelection",
    "when": "editorHasSelection"
  }
]

Development

Build from Source

cd vscode-ason
npm install
npm run build

Test Extension

1. Open this folder in VS Code
2. Press F5 to launch Extension Development Host
3. Test commands in the new window

Package Extension

npm install -g @vscode/vsce
vsce package

This creates a .vsix file you can install locally or publish to the marketplace.

What is ASON?

ASON (Aliased Serialization Object Notation) is a token-optimized JSON compression format designed specifically for Large Language Models (LLMs).

Key Features:

• 20-60% token reduction on average
• 100% lossless round-trip fidelity
• Human-readable format
• Multiple compression techniques (uniform arrays, object references, value dictionary, path flattening)

Learn More:

• ASON GitHub
• Interactive Demo
• Documentation

🚀 Publishing

To release a new version:

# Run the release script
./scripts/release.sh

# 1. Select version bump (patch/minor/major)
# 2. Update CHANGELOG.md when prompted
# 3. Confirm push

# GitHub Actions will automatically:
# - Build the extension
# - Create .vsix file
# - Create GitHub Release with .vsix attached

# Then manually publish to VS Code Marketplace:
npm run publish

📝 License

MIT © ASON Project Contributors

🤝 Contributing

Contributions welcome! Please open an issue or pull request.

🔗 Links

• GitHub: https://github.com/ason-format/vscode-extension
• Issues: https://github.com/ason-format/vscode-extension/issues
• ASON Core: https://github.com/ason-format/ason
• VS Code API: https://code.visualstudio.com/api